If you had a choice: Acceleration or Distance?

[Luke42]

I'm glad Tesla disagrees. ie Ludicrous.

Ludicrous mode is an option, and one i plan to forgo.

Seriously, any car that can take a 2nd generation Prius at a stoplight has more acceleration than I need. (We owned a 2nd generation Prius for 12 years.)

I'm sure I'll enjoy the extra acceleration that the Model 3 provides now and then, but I don't need it and I don't plan to pay extra for more.

 

[JeffK]

Tesla to date tends to contradict all that going with sleek and range. Adjusting the motors and how the battery power is used so that a regular (8 sec/60 mph) acceleration is the base would likely greatly increase the range.

As for the 2nd most important factor after increasing range, that would be improving recharge time.

No, it's true that higher energy densities allow higher boxier vehicles to be electrified. The higher energy density is needed to get ranges equivalent to what the sleeker designs get today.

The other sentence about adjusting the motors isn't really going to add a significant real world range and is therefore not worth doing. As previously stated you can accelerate more slowly whenever you want.

 

[EaglesPDX]

No, it's true that higher energy densities allow higher boxier vehicles to be electrified..

It allows lower, wider, shorter, taller vehicles to be electrified. In other words it's meaningless to the point of which is preferable speed or range.

 

[JeffK]

It allows lower, wider, shorter, taller vehicles to be electrified. In other words it's meaningless to the point of which is preferable speed or range.

The coefficient of drag on a vehicle has everything to do with range...

 

[Red Sage]

I just wonder.... I the M3 was known to have a range of 500+ miles per charge....if everyone responding would now say..... 500 miles is enough. Or are people mile mongers? I want more, more, more, more....

I think that: 1) people will always want more; and 2) Elon will always want to show off -- by offering MORE.

At some point, range will be so much higher on a fully electric car that even a Prius with a 25 gallon fuel reserve would trail behind by 50%.

For me? Something between 2,500 and 6,000 miles range would probably be... enough. But Imagine a time when cars roll out of Fremont displaying a 60,000 mile available range.

 

[Red Sage]

I'd GLADLY take an 8-second 0-60 in order to get 30% more range. GLADLY. That would make the car unquestionably better. 0-60 is not an important feature in a car.

Once again, that isn't how it works. You would also have a MAXIMUM speed of 60 MPH. And you can do that anyway. Just don't stomp on the GO Pedal. Apply acceleration as quickly or slowly as you like, don't exceed 60 MPH, and you will probably be able to travel 300 miles. If you want to drive 90+ MPH, up a 6% grade, through hub-deep snow, in sub-freezing temperatures, with a 60 MPH headwind for 300 miles, both ways...? You are out of luck without an incredibly higher capacity battery pack. You aren't going to magically 'get 30% more range' by varying the acceleration profile from sub-3 seconds to plus-8 seconds, without any other concessions.

 

[EaglesPDX]

The coefficient of drag on a vehicle has everything to do with range...

But the issue raised and commented was about energy "density" not wind resistance.

 

[Red Sage]

You didn't mention what you would take the 8-second time in exchange for. Is that a 30% decrease in 0-60 time?

I'm sure almost all people would agree with you. You're saying you want to go from a 5.6 to 8.0 0-60 in exchange for 279.5 miles of range instead of 215. The problem is that that's not even an option we have. First, looking at the actual acceleration vs. range graph, we only know one point - on a Model S, to go from a 4.2 to 3.1 0-60 time (a 26% improvement, costs you 8.8% of range (294 to 270). Actually, we know two points. Going from 3.1 to 2.8 (Ludicrous mode; an improvement of 10% from a P90D) costs you 0% in range. That's right, acceleration is "free" in terms of EPA range, for this one datapoint. And these two points are already at the very high end of "how much faster can we push this thing." We just have no idea how much range could be gained if the motor, inverter, battery, and gear ratios were all perfectly sized to meet 8.0s 0-60, and no better. I suspect it's less than a 5% improvement (226m) on the stated 215m range of a base 3 doing a 6.0 0-60. Maybe even smaller.

Yes, Elon likes fast cars. But that's only partially why the Model 3 will be a fast car. It's just so danged easy to make the car fast when you've already designed and built high efficiency batteries, inverters, and motors in order to allow efficient long range travel, with quick recharging, that why would you not?!

Don't forget that the number one factor affecting range is how fast you drive. If you're going 90mph constantly, your battery will be dead very quick, regardless of if you got to 90 in 5 seconds or 5 minutes. If you drive 35mph constantly, it will last a very long time, even if your initial accelleration was in 1.5s.

Exacto-FRIGGIN-mundo!

 

[JeffK]

But the issue raised and commented was about energy "density" not wind resistance.

Boxier vehicles by definition have a higher wind resistance... hence higher energy densities are needed to both keep the weight down and allow those types of vehicles the range today's vehicles have. Whether it's a semi-truck, pickup truck, or a big child molester van, everything will benefit from higher energy densities.

 

[Red Sage]

I don't "need" it. Given the hypothetical choice, I'd give up acceleration for increased range.

The thread title specifically says "If you had a choice between acceleration or distance". It doesn't say top speed. Regardless, my thoughts on top speed mirror those on acceleration.

Given the hypothetical choice: There is no spoon.

 

[Red Sage]

More like 450-500 miles EPA. Cold air, cold tires, heater running, highway speeds? Or pushing through snow plus heater use? It can easily take 450 to 500 Wh/mile in such conditions.

I'd be content with a more reasonable 180-200 miles in all weather conditions. If the weather is very poor I am much less likely to take a long trip anyway. And that range is more than enough for routine local driving in winter conditions.

Am I the only person who automatically drives at least 20 MPH less than the posted limit during inclement weather? In my experience with snow, even doing 45 MPH on the highway was a lot faster than the people pulled over to the shoulder, or sitting in the ditch.

 

[ccutrer]

Am I the only person who automatically drives at least 20 MPH less than the posted limit during inclement weather? In my experience with snow, even doing 45 MPH on the highway was a lot faster than the people pulled over to the shoulder, or sitting in the ditch.

Depends on how inclement, but no. And typically I'm watching my mirrors (and reverse camera this upcoming winter!) for the idiots behind me that forget that the coefficient of friction is highly reduced in wet conditions. I've actually discussed with some friends that I wish Tesla had automatic emergency scoot-forward, to avoid getting rear-ended!

 

[Red Sage]

I think that once they've completely resolved any range issues, they keep working on battery tech to make it cheaper, and lighter. Lighter also means cheaper (need less energy to move the same vehicle), so that's a double whammy.

Heh. This is sort of a chicken and egg situation, only in a logarithmic matrix with several different degrees of chickens and levels of eggs. Sort of a multi-dimensions tug of war. From my point of view, Tesla Motors will completely resolve range issues by making battery technology less expensive and more energy dense, so that vehicles can weigh less. It is all part of the same equation, which also includes temperature controls, state of charge cycles, and shock resistance.

 

[EaglesPDX]

Boxier vehicles by definition have a higher wind resistance...

Amazing facts we learned in grade school...but again...nothing to do with the comment about higher energy density batteries increasing range which applies to all vehicles.

in case of T3 and the desire for more range over greater acceleration one would have to assume the battery is constant so the greater range would come from smaller, more efficient motors and controls geared toward range that would not give as great an acceleration but would give greater range.

 

[Red Sage]

Depends on how inclement, but no. And typically I'm watching my mirrors (and reverse camera this upcoming winter!) for the idiots behind me that forget that the coefficient of friction is highly reduced in wet conditions. I've actually discussed with some friends that I wish Tesla had automatic emergency scoot-forward, to avoid getting rear-ended!

Interesting. People seem to complain about the current form of automatic scoot-forward, where the car on Autopilot seeks to 'close the gap' in traffic a bit more aggressively than they would prefer. It seems they would prefer there was an automatic back off instead -- so that the car slows in traffic at a quicker rate, thereby leaving a greater gap between your own vehicle and slower moving, or stopped, traffic ahead of you. In most situations, I rather agree with Enzo Ferrari, "What's behind you, doesn't matter."

To me, inclement weather is anything without several miles of visibility and temperatures substantially over 75° Fahrenheit. To put it another way? Heavy fog, heavy rain, heavy sleet, hail, gusting winds, standing water, black ice, snowdrifts -- all of these pass for inclement weather in my mind. I learned that on most freeway interchanges and offramps, the yellow/amber warning signs for lower speeds can be ignored here in California -- unless it is raining. If the orange sign says '35', you can typically take the turn at 50 or more (without frightening the passengers TOO much). But in the rain, it is best to go ahead and throttle down to the 35 MPH recommendation. Driving across I-40 in Tennessee, I learned that regardless of conditions you should ALWAYS obey the warning signs. Their offramps are much shorter and steeper, so you can get into trouble REAL quick.

 

[dgpcolorado]

Am I the only person who automatically drives at least 20 MPH less than the posted limit during inclement weather? In my experience with snow, even doing 45 MPH on the highway was a lot faster than the people pulled over to the shoulder, or sitting in the ditch.

One should slow down in snow but typically the savings in drag from slower speeds is more than made up for by the increased energy to push through snow. A lot depends on the amount and type of snow. Warm wet snow can be slick and heavy to push through. Very cold* dry snow often makes for decent traction IME. But there is no way I am going to take a 300+ mile road trip if roads are snow packed; I can wait for better weather.

I mostly drive clear roads even in winter but temperatures around 20ºF (-7ºC) are common here and really increase energy usage due to increased drag, rolling resistance, heater use, and the like. And it gets worse with cold mornings below 0ºF (-18ºC). The coldest I can recall was about -22ºF (-30ºC), which is probably no big deal to someone in Minnesota, Canada, or Alaska.

"Real world" range depends a lot on what sort of conditions one is assuming!


* For me, "very cold" is when the snow is "squeaky cold" (about 9ºF or less). Walking on squeaky cold snow is one of life's joys! It also makes for good skiing.

 

[Garlan Garner]

One should slow down in snow but typically the savings in drag from slower speeds is more than made up for by the increased energy to push through snow. A lot depends on the amount and type of snow. Warm wet snow can be slick and heavy to push through. Very cold* dry snow often makes for decent traction IME. But there is no way I am going to take a 300+ mile road trip if roads are snow packed; I can wait for better weather.

I mostly drive clear roads even in winter but temperatures around 20ºF (-7ºC) are common here and really increase energy usage due to increased drag, rolling resistance, heater use, and the like. And it gets worse with cold mornings below 0ºF (-18ºC). The coldest I can recall was about -22ºF (-30ºC), which is probably no big deal to someone in Minnesota, Canada, or Alaska.

"Real world" range depends a lot on what sort of conditions one is assuming!


* For me, "very cold" is when the snow is "squeaky cold" (about 9ºF or less). Walking on squeaky cold snow is one of life's joys! It also makes for good skiing.

Sounds logical to me.

 

[Automaton]

Without both range and acceleration, I would not buy any car. If all I wanted was range, I would have bought a Volt since it has an ICE backup to cover long trips. Or the Bolt... I think that's the newest slow ugly American electric car with decent range? However, that thing is slower than snot. If all I wanted was speed, I did almost buy a Subaru WRX. The WRX gets terrible gas mileage though, and the sales guys don't allow WRX test drives, so I swore off the WRX. I have driven slow cars (7s+ 0-60mph) up until my current car because that's all I could afford. My current car does 0-60 in 4.9s, which is plenty fast for me and I wouldn't want to go noticeably slower than that. I'm hoping the dual motor Model3 can come close. It's not about racing or speeding. I typically cruise along with the flow of traffic around me. It's about maneuverability in respect to other cars when needed and a little bit of onramp fun here and there. If I theoretically had to sacrifice a little range (while still remaining comfortably usable) to get acceptable acceleration, I would be ok with that.

 

[Jersey Shore Tom]

However, that thing is slower than snot.

That's one slow car! Sneeze Travels 100 mph

 

[Garlan Garner]

That's one slow car! Sneeze Travels 100 mph

That's disgusting. I'm glad my M3 is going to have the biohazard filter built in.